Get property value from C# dynamic object by string (reflection?)

Imagine that I have a dynamic variable:

dynamic d = *something*

Now, I create properties for d which I have on the other hand from a string array:

string[] strarray = { 'property1','property2',..... }

I don't know the property names in advance.

How in code, once d is created and strarray is pulled from DB, can I get the values?

I want to get d.property1 , d.property2.

I see that the object has a _dictionary internal dictionary that contains the keys and the values, how do I retrieve them?

I don't know if there's a more elegant way with dynamically created objects, but using plain old reflection should work:

var nameOfProperty = "property1";
var propertyInfo = myObject.GetType().GetProperty(nameOfProperty);
var value = propertyInfo.GetValue(myObject, null);

GetProperty will return null if the type of myObject does not contain a public property with this name.

EDIT: If the object is not a "regular" object but something implementing IDynamicMetaObjectProvider, this approach will not work. Please have a look at this question instead:

How do I reflect over the members of dynamic object?

This will give you all property names and values defined in your dynamic variable.

dynamic d = { // your code };
object o = d;
string[] propertyNames = o.GetType().GetProperties().Select(p => p.Name).ToArray();
foreach (var prop in propertyNames)
{
    object propValue = o.GetType().GetProperty(prop).GetValue(o, null);
}

Hope this would help you:

public static object GetProperty(object o, string member)
{
    if(o == null) throw new ArgumentNullException("o");
    if(member == null) throw new ArgumentNullException("member");
    Type scope = o.GetType();
    IDynamicMetaObjectProvider provider = o as IDynamicMetaObjectProvider;
    if(provider != null)
    {
        ParameterExpression param = Expression.Parameter(typeof(object));
        DynamicMetaObject mobj = provider.GetMetaObject(param);
        GetMemberBinder binder = (GetMemberBinder)Microsoft.CSharp.RuntimeBinder.Binder.GetMember(0, member, scope, new CSharpArgumentInfo[]{CSharpArgumentInfo.Create(0, null)});
        DynamicMetaObject ret = mobj.BindGetMember(binder);
        BlockExpression final = Expression.Block(
            Expression.Label(CallSiteBinder.UpdateLabel),
            ret.Expression
        );
        LambdaExpression lambda = Expression.Lambda(final, param);
        Delegate del = lambda.Compile();
        return del.DynamicInvoke(o);
    }else{
        return o.GetType().GetProperty(member, BindingFlags.Public | BindingFlags.Instance).GetValue(o, null);
    }
}

Use the following code to get Name and Value of a dynamic object's property.

dynamic d = new { Property1= "Value1", Property2= "Value2"};

var properties = d.GetType().GetProperties();
foreach (var property in properties)
{
    var PropertyName=property.Name; 
//You get "Property1" as a result

  var PropetyValue=d.GetType().GetProperty(property.Name).GetValue(d, null); 
//You get "Value1" as a result

// you can use the PropertyName and Value here
 }

string json = w.JSON;

var serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJsonConverter() });

DynamicJsonConverter.DynamicJsonObject obj = 
      (DynamicJsonConverter.DynamicJsonObject)serializer.Deserialize(json, typeof(object));

Now obj._Dictionary contains a dictionary. Perfect!

This code must be used in conjunction with Deserialize JSON into C# dynamic object? + make the _dictionary variable from "private readonly" to public in the code there

Get property value from C# dynamic object by string (reflection?)

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